C ＃ find perfect numbers, output daffodils and use of classes

Perfect number

If a positive integer is equal to the sum of all divisors except itself , Call it a perfect number .
Perfect number

for(int i = 1; i < 1000; i++)
{
int sum = 0;
for(int j = 1; j < i; j++)
{
if (i % j == 0)
{
sum += j;
}
}
if (sum == i)
{
Console.WriteLine(i);
}

Code

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace ConsoleApp3{    class Program    {        static void Main(string[] args)        {            for(int i = 1; i < 1000; i++)            {                int sum = 0;                for(int j = 1; j < i; j++)                {                    if (i % j == 0)                    {                        sum += j;                    }                 }                if (sum == i)                {                    Console.WriteLine(i);                }                           }            Console.ReadKey();        }    }}

result

Previous perfect numbers within 6 28 496

Output all Narcissus

The number of daffodils is a three digit number , The cube sum of its digits is equal to the number itself
daffodils

int a, b, c;
for(int i = 100; i < 1000; i++)
{
a = i / 100;
b = i / 10 %10;
c = i % 10;
if (a * a * a + b * b * b + c * c * c == i)
{
Console.WriteLine(i);
}

Code

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace ConsoleApp4{    class Program    {        static void Main(string[] args)        {            int a, b, c;            for(int i = 100; i < 1000; i++)            {                a = i / 100;                b = i / 10 %10;                c = i % 10;                if (a * a * a + b * b * b + c * c * c == i)                {                    Console.WriteLine(i);                }            }            Console.ReadKey();        }    }}

result

The number of daffodils is 153 370 371 407

The use of the class

Code

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace ConsoleApp6{    class Student    {        public string name;        public string sex;        public int age;        public Student(string name, string sex)        {        }        public Student(string name, string sex,int age)        {            this.name = name;            this.sex = sex;            this.age = age;        }        public void Inderduce()        {            Console.WriteLine(" My name is "+this.name+" I am a "+this.sex+" Child , I this year "+this.age+" year ");        }    }    class Program    {        static void Main(string[] args)        {            Student s1 = new Student(" Xiaohua "," male ",20);            Student s2 = new Student(" floret "," Woman ",18);            s1.Inderduce();            s2.Inderduce();            Console.ReadKey();        }    }}

Output results